In a routine urinanalysis, a urine specimen from a jar or the like provided by a patient is transferred into a test tube or other enclosure for transport to a laboratory. When the specimen arrives at the laboratory, a second transfer of a given quantity of the urine is made to a centrifuge tube, designed to be held in a centrifuge machine. After centrifuging, sediment collected at the extended end of the tube is then in turn analyzed as by visual inspection as well as by placing given volumes on a microscope slide.
The foregoing involves much handling of various tubes and enclosures as well as transfer of the urine specimen itself, all deleterious to sterile conditions.
Improvements in urinanalysis have been effected by provision of multi-purpose tube structures wherein the same tube that is used to transport a urine specimen or other liquid specimen from a doctor's office or hospital to a laboratory is also usable as a centrifuge tube so that no transfer is necessary in carrying out the centrifuging step. In addition, it has been proposed to provide a cap structure on a centrifuge tube which will collect liquid and sediment in a known amount so that a transfer from the cap directly to an examination slide can be effected.
U.S. Pat. No. 3,796,542 illustrates one example of a tube serving several functions. The particular tube illustrated has a helical corrugated wall structure functioning in the manner of a bellows so that liquid specimens can be drawn into the interior of the tube. However, the device in this particular U.S. patent has a syringe structure on its top to be used as a fluid or liquid conduit in passing a specimen into the bellows-like wall structure. This syringe-like passage remains as a part of the overall container. Sediment is removed from the bottom of the container after centrifuging by piercing a membrane.
U.S. Pat. No. 3,460,529 illustrates a sterile device for extracting urine samples and the like wherein there is disclosed the concept of a cap structure for collecting a given amount of sediment for subsequent examination.